Email: add a "select all" or "delete all" to clear mass messages

I just wasted 20 minutes of my life trying to empty out my "Sent" messages. I have courses in which a few hundred students receive a general email announcement or reminder from me, & I don't need to keep an individual copy of every single one of those emails. Right now, I can only delete 7 messages at a time, as that are all that fit on the screen. If I scroll down to select more messages, the ones at the top that are no longer shown get de-selected, for some reason.

Nadine, from your idea description, it's clear that you've already followed the instructions at the end of the How do I use Conversations as an instructor? lesson and are looking for an enhancement to the feature on the order of a button that selects all conversations/messages across all pages of the Inbox; I'm providing the link to the documentation so that anyone coming across this idea knows that there is a method for selecting multiple conversations on a single page.

Also, just wondering: when you selected the messages, did you use the scroll bar? I find that if I pull the left panel's scrollbar down, I can select multiple messages beyond those that fit on the page.